We examined the effect of tympanic neurectomy on the clinical symptoms and secretory function of the parotids in 13 patients with chronic parotitis or sialadenosis for 3 years. Each patient had significantly fewer complaints immediately after the surgery. In quite a few patients the improvement was transient only. Three years after neurectomy 3 of the 10 examined patients were free from complaints and 4 further patients had less severe complaints than before the surgery. Neurectomy was followed by a significant decrease in parotid flow rate and an increase in the sodium concentration of parotid saliva, while potassium concentration showed a slight decrease. Three years after the surgery the flow rate and the sodium concentration were moderately higher than before that. There was a significant, long-lasting change in the amylase activity of parotid saliva; 3 years after neurectomy it attained one-third of the preoperative value. A pharmacological test, carried out 3 years after neurectomy in 2 patients, suggested parasympathetic reinnervation of the parotid.